I suppose the first step is to try something like reading the raw disk (with dd or equivalent) to see if you can extract "enough" of it to make a go of recovering your own data. If it's well and truly broken, then you're dealing with the sort of people who keep clean rooms around and charge big bucks. Never used one myself, although there was a NY Times article a couple years ago that you may be able to hunt down. If the companies mentioned then are still in business now, that's a good sign...